script to update XML file data

Question

I need to update value field by searching the avp name in below .xml file .

 <avp name="CC-Request-Type" value="1"> </avp>
  <avp name="CC-Request-Number" value="0"> </avp>
  <avp name="Subscription-Id">
  <avp name="Subscription-Id-Type" value="0"></avp>
  <avp name="Subscription-Id-Data" value="4081234567"></avp>
  <avp name="Framed-IP-Address" value="0xXXXXX"> </avp>

I need to search row has "Framed-IP-Address" update value filed 0xXXXXX to 0xYYYYY

Please let me know how to do using sed or AWK or shell script any input to do this will be really helpful.

Answer 1

The right tool for this is something that is XML-aware.

XSLT (via xsltproc) or any general purpose scripting language at your disposal (Python, Ruby, Perl, node.js, even PHP-CLI) are examples of suitable tools to modify XML. sed or awk or bash script are examples of unsuitable ones.

Here's an XSLT-based solution

<!-- modify-Framed-IP-Address.xsl -->
<xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
  <xsl:template match="node() | @*">
    <xsl:copy><xsl:apply-templates select="node() | @*" /></xsl:copy>
  </xsl:template>

  <xsl:template match="avp[@name = 'Framed-IP-Address']/@value">
    <xsl:attribute name="value">0xYYYYY</xsl:attribute>
  </xsl:template>
</xsl:stylesheet>

used as

xsltproc modify-Framed-IP-Address.xsl input.xml -o output.xml

will replace the attribute and save the result to output.xml.

If you don't want to use XSLT, use a scripting language you know. A Python-based solution, for example, would be in the same order of less-then-10 lines of code for such a simple task. See this thread to get an idea on how to start.

Answer 2

Give a try to this sed command,

sed '/<avp name=\"Framed-IP-Address\"/s~value=\"[^"]*\"~value="0xYYYYY"~g' file

Through awk,

awk '/<avp name=\"Framed-IP-Address\"/{sub(/value=\"[^"]*\"/,"value=\"0xYYYYY\"")}1' file